Same here, win7 64bit (c:\games\aurora), I get the opening error with v5.3 (error 76) but plays ok after I dismiss the error box, with v5.4 I get error 76 (path not found) which i can dismiss, but its followed by error 91 (Object variable or With block variable not set) and I cant get rid of that one, it just replaces the error message if I click ok or the x to get rid of it, need to kill the aurora process to stop it. I patched the 5.3 version, and later replaced the v5.4 files with the v5.3 files again and it works fine (once past error 76) - v5.2 worked as well - no errors at all with that version.